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Jim P
05-26-2004, 17:03
I have to admit that since last summer when I rebuilt my engine, I have been running without a pyrometer.

Since I just bought a 30' 5er, I decided to get one. I installed the probe in the crossover pipe about 3" below the left manifold. When I took it for a short drive, it would easily hit 1200 degrees within seconds of me putting my foot to the floor. What is it going to do on a hot day with my 5er hooked on?

ucdavis
05-26-2004, 17:29
Sounds a lot like the experiences of Journeydog. His would hit 1250 pretty easily, but since his motor was in a 16,000 pound vehicle, any good goose on the gas and he hit 1450. But not too many times.
If this is a no-load 1200 degrees you need service on the cooling system, probably starting w/the space between AC condensor & radiator, and finishing w/an operational check of the AC electric fan.
Sometimes theAC fan won't kick on and you get little airflow across the radiator to heat up the viscous clutch on the engine fan. No heat on that & it won't come on cuz it thinks all is cool.
Start w/a good cleaning of the radiator & condensor.

Jim P
05-26-2004, 17:44
I don't think it is a problem with the cooling system. I only drove it four miles and it hit 1200 degrees while going up a hill about 2 miles from my house. The coolant wasn't even warm enough for the fan clutch to kick in.

I'm thinking that it is just getting too much fuel. It smokes like a Mack truck until the boost comes up.

gmctd
05-26-2004, 20:13
You need more air or less fuel - black smoke means hi EGT's.
'Chip' plus hi flow injectors plus max FSD resistor.

Is Boost delayed - black smoke until boost comes up?
Normally, Boost spools up over 10psi off-idle with engine at normal running temp.

Check your Intake Air Temps in the manifold at 15psi - if vehicle is moving temps should be around ambient for air-to-air, or less for chilled water-to-air cooling.